The purpose of this invention is to provide means for delivering fabric conditioners to clothes, fabrics and other textile materials (for ease of reference, such items are referred to herein as "clothes") which are washed in washing machines. (Herein, unless stated otherwise, "conditioner" and "conditioners" include fabric softeners, anti-static agents, deodorants, perfumes and other fabric conditioners. Fabric softeners are the primary concern of this invention.)
Virtually everyone is aware of the pleasing feel and effect a truly soft towel, shirt, pair of socks, undergarment, etc. has when brought into contact with their body. However, when such items are washed with current detergents, the softness quickly disappears and the items become coarse. (Herein, "detergents" include soaps as well as detergents.) This is probably a result of mineral deposits, precipitation of certain components in the detergents and other factors.
Attempts to avoid such coarseness have been made by adding fabric softeners to detergents, such as by mixing dry or liquid detergents and softeners. This approach has also proven to be unsuccessful and can even increase the coarseness. One explanation for the latter result can be found in U.S. Pat. No. 4,659,496 (Amway Corporation):
"Most fabric softeners/antistatic compounds provide softening and antistatic action by depositing cationic particles onto fabric surfaces. They impart desirable qualities such as pleasing, tactile properties, reduction of static electricity and the adherence of dirt and dust particles, reduction of fabric wrinkles and generally permit treated fabrics to be more easily separated following the drying cycle. Typically, fabric softeners/antistatic contain a cationic quaternary ammonia compound. These positively charged particles, however, interfere with anionic soil components as well as with anionic surfactants which are present in many conventional detergent compounds. This charge attraction between cationic and anionic components forms unwanted precipitates which may accumulate on fabric surfaces commonly in the form of redeposited soil. In order to eliminate this source of interference, it is desirable to keep anionic and cationic components separated during the laundering process." (Emphasis supplied.)
The art has long sought a satisfactory solution to the above problem. While the art has developed a large number of softener and other conditioning agents (described below), none have worked properly when mixed or otherwise packaged with detergents. The only known method of achieving acceptable conditioning is, as mentioned above, that of introducing the conditioner separately into the washing machine by hand after the detergent has been rinsed out--and this method is, quite obviously, impracticable for most persons.
To explain, some years ago, certain automatic washing machines had devices designed to release conditioners at the "right" time, i.e., after the detergent had been rinsed away by the first rinse cycle. Such machines then released the conditioners during the second rinse cycle. In this manner, the conditioners did not react with the detergent and, moreover, the conditioners were thereby allowed to permeate the clothing. Consequently, the clothing, when dried, were very soft and, when anti-static agents were included (as is usually the case)--free of static cling.
For whatever reason, few if any automatic washers currently sold have such conditioner delivery devices. Accordingly, manufacturers of detergents have been forced to use other modes of introducing conditioners into washing machines. (There are several companies in the United States which continue to sell liquid conditioners. However, such conditioners can only be properly used if the person washing his or her clothes has a timer or sits and watches the automatic washer until it begins its second rinse cycle to pour the conditioners in. Alternatively, the person can wait until the washer completes all cycles and shuts down, at which time the person can pour the conditioner onto the clothes, move the control to the second rinse and re-start the machine--all at a waste of time and convenience. Since this is impractical for almost everyone, especially with so many women working, the bottle liquid (or dried) conditioners now on the U.S. market which, by their own labels require their conditioners be introduced only after the first rinse, do not solve the delivery problem.
A number of companies have simply mixed conditioners with detergent. See, for example, U.S. Pat. No. 3,936,537. None of these mixtures provides adequate conditioning. Indeed, the clothes so treated are harsh to the touch, undoubtedly because the conditioners react with the detergents to form precipitates.
Companies have also attempted to solve the problem by impregnating conditioners on or within pouches or on conditioner sheets for use in the washer and/or the dryer, See U.S. Pat. Nos. 4,733,744 and 4,659,496; 4,229,475; 4,229,475; 4,308,306; 3,686,025; 4,255,484; 3,936,538; 3,632,396; 4,356,099; 4,389,448; 4,659,496; and 3,896,033. These do not condition clothes adequately. Those configurations which mix detergents and conditioners suffer from the drawbacks noted above. In addition, the highly promoted "dryer sheets"--which are impregnated with conditioners--are very inadequate. Undoubtedly, this is due in part to the fact that a small sheet in a large mass of clothes in a tumble dryer simply cannot release enough conditioners--especially softeners--to improve feel.
Another approach is exemplified by U.S. Pat. Nos. 4,082,678 and 3,947,971. The '678 Patent discloses a so-called "inner receptacle" containing the conditioners which "serves to prevent the fabric conditioning composition from being released to the fabrics until the rinse cycle of the washer and the drying cycle of the dryer. The receptacle thus must have at least a part of one wall which is water soluble/dispersible but is unsolubilized during the wash cycle by the maintenance of a sufficient electrolyte level and/or the appropriate pH." (Col. 6, lines 33-40) It is not believed that the system of the '668 Patent ever reached commercial success.
The '971 Patent discloses a softener in a tablet which is encased in sheets. Again, it is believed that this system was never successful. See also U.S. Pat. No. 4,348,293.
Thus, prior systems do not adequately perform as means to deliver conditioners.